This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Glycosaminoglycans (GAGs) are a structurally very diverse set of carbohydrate polymers found both free and attached to protein at cellular surfaces. They mediate signaling events as well as numerous other interactions between a cell and its environment. Characterizing oligomers derived from these polymers is a challenging problem that can be addressed by high resolution MS methods. New FTMS facilities at the Resource are ideally suited to this research.